Hob grinding machine



arch 21, 1933. c. G. OLSON 1,991,926

' nos GRINDING MACHINE Filed Feb. 16, 1928 6 Sheets-Sheet 1 f/VL E/V 70/? CARL. 0450M 4 T -ys March 21, 1933. c. G. OLSON I 1,901,926

HOB GRINDING MACHINE Filed Feb. 1a, 1928 s Sheets-Sheet 2- M l I A Marsh 211 1933. c. e. OLSON HOB GRINDING MACHINE 6 Sheets-Sheet 3 Filed Feb. 16, 1928 March 21, 1933. Q OLSON 1,901,926

HOB GRINDING MACHINE Filed Feb. 16, 1928 6 Shee sheet 4 I JPVI/AVV 70A CARL 6-.- 04 so/v Arrns? Marsh 21, 1933 c. (a. OLSON HOB GRINDING MACHINE Filed Feb. 16, 1928 6 Sheets-Sheet 5 Arrysf d ssented 2i, i i? moses, H4315, A 60.

llngslicotion tiled Economy 16, secs. aerial it; fl-hd'ii'r'h This invention relates to meteriel working machines, end particularly to machines such as hob grinders end the like, wherein the won-ls is ieciprocsted through the agency is oi e lend screw. 7

in the manufacture of hobs it is common )lilCtlCQ to employ the some machine for grinding hoh-s of varied diameters, and in order to employ such o mechine in this men in ner the pitch oi the lead screw thereof which sctnctes the work carrier must conform to the 'eniel pitch of the hoh to be ground. This will be readily op nrent when it is understood that the helix singles of holes is very in accordance with their'dmmetccs and consequently the difiercnce hetween the non incl pitch end the esisl pitch correspond ingly varies. While the requirement for the normal pitch may he the some for holes of diderent diameters it is necesss to chsng'e the csinl itch in eccordsnce with e change in the ho diemeten'sndthis exinl pitch of the hob is cal to the pitch of the J lesdscrew which ectustes the work carrier st in grinding machines heretofore used. Hencoin order to ads t such machines to cover at wide range of ends, it is necessary to provide s large number of interchangenlole lend screws, and obviously this repreeo sents n large investment, and the intei changing on these screws requires the expenditure oi considerable time in setting up the machine tor each job.

An object of my invention is to' occlude.

the necessity of frequently interc angling lend screws hy roviding e compcnsstin device which will serve to alter the axis movement of the work from that of the movement ordinarily. imported to the work during each revolution of the lend screw,

and thereby enable the use of one load screw of n predetermined pitch to reduce an infinite number of leads wit in a certain renge.

Another object of my invention is to provide n compensating device of economical and rigid construction which may be readily superimposed upon the lead screw of a grinding machine, or any other machine of W like nature, and which may. be easily edjusted to accurately efiect s, diderentiol movement between the heed screw end its compsnion out within very close limits.

llneddition to the shove mentioned charasteristics, it is it further object oil my into vention to provide o machine in which a pair of o positely disposed grinding wheels are cmp oyed to simultaneously grind oyposite surieces oi the hole teeth, and this represents on improvement over the rinding meto chine disclosed in my copen ing epplicetion, Serial No. 86,206, filed February 5, 1926 wherein a single grinding wheel is employed which may he reversed in order to rind both surfaces oi. the hoh teeth.

further object is to srmnge the grin ing wheels so that the wheels stnrt simultsneously end likewise simultaneously complete the grinding operation, therehy requiring minimum time to complete the shots to tive stroke or movement of the wheels, and this feature re resents on improvement over the machine disclosed in my Potent No. 1,259,770 dated March 19, 1918 wherein at number of grinding wheels are positioned on the same side of the hoh.

Withthe foregoing and other ohjects in view, which will nppeer in the following descri tion, the invention resides in the novel com instion and errengement of ports and so in the details of construction hcreinnftcr de scsihed and cleinied.

In the accompanying drawings:

Figure l. is an elevotionsl View of s grinding machine which represents one embodiso ment of my invention, e portion of the machine bed end ironic being broken sway to disclose structure otherwise hidden.

Figure 2 is s'tz'snsverse verticol sectional view taken on the line 2'-2 of Figure 1. Figiire 3 is o plen view of the machine disclosed in Figure 1.

Figure 4 is an enlarged fragmentary view of the leed screw and associated compensating device as viewed in Figure Ls portion of the cooperating arts thereof being bro ken away to more c eerly disclose the internal structure.

Figure 5 is as detailed vertical sectional view taken on the line of 5--5 otLFigure 1.

Figure 6 is a vertical section taken on the lin 66 of Figure 4.

1 line 7 of Figure 4.

Figure 8 is an enlarged plan view of the lead screw and asociated mechanism disclosing the relative position of the various elements at the beginning of the effective stroke of the work spindle.

Figure 9 is a plan view, similar to Figure 8, disclosing the relative position of the machine elements as the work spindle approaches the completion of its operative stroke.

Figure 10 is a perspective view of the elements comprising the compensating device in association with the cam member carried by the lead screw, and,

Figure 11 is a detailed view of the mechanism for imparting a reciprocatory movement to the grinding wheels and this mechanism represents an alternative form of the mechanism disclosed in Figure 2, which is em loyed for the same purpose.

eferring now to the drawings wherein like numerals have been employed to designate similar parts throughout the various figures, it will be observed that a machine bed 1 supports a frame 2 and rising from and secure to one end of the frame 2, Figure 1, is a split bearing 3 which provides a mounting for a work spindle 4. The work spindle 4 is formed integral with a lead screw 6 and supports a gear 7 which engages an elongated pinion 8. Rotation is imparted to the pinion 8 through the agency of a chain 10, and it will be observed that the lead screw 6 is rotatable within a suitable s lit nut 11. The split nut 11 is secured to t e upper surface of a block 12, which is mounted within guide-ways 14, Figure 10. formed in the u per portion of one end of the frame 2. rom the foregoing it will be clear that upon the rotation of the lead screw 6 within the split nut 11 said screw and the work spindle 4 will be moved axially and a hob 15 supported at the reduced outer extremity of the work spindle 4 will likewise experience the same axial movement. This hob 15 is secured to the spindle by means of a suitable tightening nut 16 and is adapted to be advanced between a number of grinding wheels 18.

These grinding wheels 18 are supported by spindles 19 rotatable within holders 20,

which are mounted upon companion pedestals 22. The spindles 19 are rotated by means of suitable belts 23, which extend between sheaves 24 and driving pulleys or sheaves 26 carried by a shaft 27, Figures 1 and 2, mounted within the lower portion of bed 1. Each 01' the pedestals 22 which support the spindle holders is mounted upon a platform which is mounted upon a slide ,30 and thus the holder is adjustable in a re 7 is a vertical section taken on the direction arallel with the axis of the work spindle 4 y means of a hand wheel 31, F igures 1 and 2 which rotates a. screw 32. The

slide 30 is adjustable horizontally toward and away from the work by a hand wheel 33 which actuates a screw 34. Each of the slides 30 is supported by a table 36, Figure 2, which is provided with a depending lug 37 and coil springs 38 operate to urge the tables 36 outwardly, thereby maintaining engagement of the depending lugs 37 with a bell' crank arm 40. A cam 41, Figures 1 and 2, is supported at the extremity of a drive shaft 42 and engages a pivoted finger 44. It is to be understood that upon each rotation of the cam 41 the finger 44 will experience a downward movement against a block 45, which rests within a yoke member 46. Laterally extending portions of the yoke member 46 engage bell crank arms 48 and thus during each rotation of the cam 41 the arms and 48 will be actuated in response to the movement of the yoke 46 and the tables 36 will be moved inwardly. The cam 41 is timed to cause the inward movement of the tables 36 in accordance with the position of the relieved surfaces on the table of the hob 15., the reciprocation of the grinding wheels 18 being similar to the movement experienced by a tool in a conventional backing-olimachine. The position of the block 45, which rests upon the yoke 46, may be adjusted by manipulating a knurled screw 49 and by varying the position of the block with respect to the pivoted finger 44 the degree of reciprocating movement experienced by the grinding wheels 18 may be accurately adjusted.

Referring to Figure 11, it will be observed that a modified or alternative mechanism is disclosed which functions to reciprocate the grinding wheels 18. This mechanism employs the cam 41, a pivoted finger 50, an adjustable block 52, and a yoke 53, all of these elements cooperating in the manner just described in connection with similar parts disclosed in Figure 2. The operation of the mechanism disclssed in Figure 11 difi'ers from the mechanism already described in that bell crank arms 54, which correspond to the bell crank arms 48 in Figure 2, engage a roller 56 carried medially of the upper portion of the yoke 53. By having these arms 54 actuated from a medial point on the yoke, a similar degree of movement of each of the arms is insured. Companion arms 57 engage rollers 58 secured to tables 60 which correspond to the tables 36 disclosed in Figure 2. Coiled sp: ms 61 surrounding an eye bo 62 constantly v c "this outwardly 1 6 thereby maintain cngag nent between the rollers 58 and the iil be understood screw 6 within d a that the 1 tion oi the iced eomse the sgoiii out 11 will cause the so ported hob 15 to he moved axially heir/sen die grinding wheels 1%, It will siso he cieer that the com ii end ihe described elements actusied iherehy operebe in timed relation. to effect a predecermined movement of the grinding Wheels toward and evvey from the work. In the evens choc the axis! pit/ch of the hob 15 is the some ss ihe pitch of the iced screw D 3, rviii he eppereo s hot for each revoluiion of the screw the hob will he moved oxieiiy through c. disieiice equal to said pitch. ilowever, if ihe exiel piich of ihe hob to ground differs from the pitch of the screw e, ,esos he provided to compenfor the verisiioii iii ehe sxiei pitch of the hoh end she pitch oi ehe screw. {This eompensecing or difieremiei eiiect is eccompiished by roesiis so he described.

A compensating device or sine her mecheoisre shown in deiii in Figures 4 and 1-9 inchisive comprises e cross slide 64 which is movehie fireosverseiy of the biock 152 This cross siide 64 cerries a pin s5 3 which. projects upwez-diy ihereirom end is adopted to he engaged by the engus es of e core member so supportexiremi'iy of lead screw 5.

loci: rims '69, end during the sxiel mover-em: che iced foo has right, 1, sod e angular surface 55, ig ges she pin 65, "will ceuse said essocieed cross siide cc to he i screws o o s smog her is, "which oi cred eh 265, "When the scoegiiior goosieion is to *ihe cross siide o es shown incissive, said her, during iii slide 6 Wiii he v c he vii-eh e roller i7 Zed upon she ilms 2 medieiiy oi the 7 1 1-, and this "will cease ihs hiociz 153 and the split 11 mo'oiiced ibhereon to direci'ziore fps-raiiei with the axis 1 screw is right, Figures 8 and fee of the coexisting 4 control che degree of movement so ehs epiie rise 11 end the c '55 essocieesd chere svicheiid obthe her occupies e ceniral zero position no compeoseimg movement he transmitted to "ihe iced screw. Grsdusztioiis ere orovided she extremity of ihe piece 70, Figures Ii and e, to facilitate n sick odiusieieoi; oi the her 7%. Secure- ;to one end of she slideoie biock 12 is e depending crochet srm Z8, and interposed heicween the hreciseb 78 and s suriece oi the frame 2 is e coiled spring 80, l cod 4, which eocircies e bolt 81 The com merooer $8 is secured in position by $011 which she bracket arm 78 is siidable. T is spring 80 operates so insure contact between the roller 77 end the ectuetimg her 74. Another coiied spring S2,.Fig1ires 8 end 9, serves to oppose the outward movementof the cross slide 64:. From the foregoing description of the compenseeio device it will be understood that e di 'ereniiei or compcnseiing'movemeht is producedio obtein variations in the exiai erevei of ch-e supported hoh with reference to e given number of revohicions of the Reed screw, and thet the motion which is superimposed upon the iced screw Thy fnhecompenssving device may be varied by e. simpie sctiieting bar. By empiofing this errengemom, one load screw is e 1e to produce an infinite number of leads vviihio s megs of leads which is required in grinding hobs of diiderent sizes.

In the operation of "the descrihed apparatus AN/V81 is supplied from on electric motor 8 igure 1, or soy other suitehie means, to a belt 85, which ectuextes the she'ic 27 which supports ihe shesves 26. The motor 84 eiso carries a gear 86 which ceases the roisi-ioxi of e shsiih 88 through c suitable train of gears, end this shs'ft es cerries e. gesr $9 end on pinion $0. By manipulating a hood lever e ciiiich mechanism coriiiecied with the iower end of she lever 92 may be accosted ireiismit rotation to e drive shaft 34. Thus when izhe chiich 93 is moved to the l ft, Fieurs .1, the shaft '94 the clutch is moved to the "hi the shaft will he rotated reverse direccion. Airier securing "she ho upon Work spindie e. "he 'posiiions oi the grinding whee s is respect 'i'o ehe ieeih by moons of L rid Wheels 51 end 38, the flfiilifi lifig her 'Yi 61i mechanism is positioned in sccordsrice with the motion, must necesssiiiy he superimposed upon the lead screw to eziiieci she proper axial 'crsvei oi she hob. The hsmdie 92 is then manipulated to actuate the clutch 93 rotation is imparted to work spindle es hereiohefore descrihed. As the com member 88 moves iii-e right, Figures 8 to I inclusive, the angular surface so thereof wiii engage the pin carried by ihc cross siide i sod the iced screvv 81 will experience o decreased or increased compenseiing movement in eccordsnce "with the setting of the actuating her 74. By havin the grinding wheels srrenoed in the descrihed mariner each of ihe $516818 will begin and finish e grinding siroke simultaneously with respect he its companion wheel, and in this manner minimum time is expended in simultaneously grinding both surfaces of the hoh iaeeth. The spindies 19 of the grinding units are arranged obliquely with respect to eiris of ihe hob end in edjiistmem or" the v ihe compensating this manner the conical gz'indieg wheels 18 may be very effectively employed. Threus s the ae'sien of the cam es ried. by the shaft 42, figures the grinding l whee is ere meve eswaze' away item the work made" Nels corseh e 511m 95, spmng one 1 i tee sue e Refs, Figure 1 the 95 n-zainr r to be used ferenf: hel x sngies interehazz, wili aise pens 2:21;

capable 01 mm. 0m should eherefese be of the appended cfie Having cieseri se i I claim as new Lettez's Patent Uses, r

1 seeure Dy actuating a Work seppemb 3316i for rotating the screw, threaded fer receivin she lead screw, imposmg s cempensetimg upon the lead seiew during the reta'tien elereei within. the ehreeeie-zi means.

- 2. In ma'eriei epgsm'fis of she ciass deseziked a Bead sez'ew fer actuetisg werk suppesc means fee rotating the screw, threasled means fez re- 6 ceiving the screw isthe em' MOT/"3- ment of the screw (hiring the rotation 'zhereof, and means for imparting an mevement in the threaded means during the mistion of the lea& screw.

3. In apparatus 0f the class fiescribed previded with a lead screw *9: actuating e gwork support and means for misting the screw, threaded means for receiving the lead screw is cause the axial movement 0f the screw during the rom tion ehereef, a support for she fzhreeded means, and means for ceu ng e relative movemene between the tweeded means and the support thereor during he mission the lead screw.

4. in s of the class described provided a ieedi senew fer actuating a work support means for rotating iced sei'ew, these-flee means fer receiving *che sceew to cause the sad mevement thereof, and fer superimpesing e compensatimg axial movemene u'een the lesdfscrew,

,nn 4's. v v u, uses diesmmeu swee mesns fer 'i'eteimg means fer z'eeeivi supesim pesieg & new

is the fieed ser 5 aetefiiee thereel WW L like men's, and means is? ishe comps 2 means in aces-Edema Wifch the eempes efiec; desiweffi.

8. En mezberisfi scyew,

eennecaed s we?) screw,- sml a eempensewng device 52117311151 53 A? '5 z. .I J. I,

3y 1.131% selew e0 cause me 1e uFZEVGE In epen em 01 me We screw Ls w e Y. a. 1. L 1.?

hen peraflei w J13 QLJS me Bead s2; J7.

ree-

9. Es. mseeeiei werking 05 the class mesembed heving e Eeedi screw, 9, f sees,

2, nm: en the lead screw, a siicie ese-eezemd with the nut, an actuating member secured is the slide, 2 relief on the frame adep i'ed to be engaged by the actuating member, end means for amuse-ingthe siide in response to angular movement between said members in response to the shifting of the first member.

21. In a hob grinding machine, a rctei'y hob supporting spindle, a tool support, e grinder wheel carried by said support, means for imparting relative movement leetween 2; supported hob and. said grinder in accordance with the reliei in the teeth on said hob, and mechanism for imparting relative movement between the hob and said grinder in a direction axially of aid i, said mechanism including means shiftsloie in timed i'eletion with the actuation of the spindle, en singularly edjusteble slide member mevabie in iespense to the shifting of said means, and a member en egeeloie with the surface of said engnierliy adjustable slide member.

22. In 2, hob grinding machine, a rotary spindle for supporting a hole, e grinder sup port, a grinder wheel on said grinder SR1P= port for grinding the teeth on asuppeited hob, said snppozts being ieletiveiy moveloie axially of the suppoited hob to maintain the proper position of the grinder wheel Within the thread helix of said hob, means ios centroiiing the shove mentioned relative ezisi movement between time supp- Ji ted hob said grinder, said means ineiudiiig an cctu sting device shiiteble in a direction trans verse to the spindle axis and s second device slidebly coupied therewith, said devices being relatively slideble and opera.

\ 3, .3 I v 41 connected with at least one (PL ssie sumooits, i a J z 1 v T" m ans means 101' eiiecting seietive .ensvesse movement between said support 131 accordsince main the relie 23. In a hob 9,- spindle foe suppo port, a grinder grinder upport,

'itable in a di supported hole to nisint tien oi the grinder wiie i Wits-L helix of e hob, c D

tinned reistive movemen ing a Siiilo device sh W a transveise the axis, an ed ostsioie slide emeei' mounted on s device, and means siidebiy coupled with ea slide meaneer and adapted to be shifted in direction longitudinally of the spindle response to the movement e'gpe ienceel by said slide member, and means for lZL'APQLE JlH-Q relative tsensverse movement ti grinder and the supp-sited bob in secessiance with the i'eliei en nab teeth.

24. In a hob geinding machine, s

eoigeee lllil 

